CNC machining vs injection molding: cost comparison
Short answer: CNC has no tooling cost but a high, flat unit price; molding front-loads cost into the mold and then runs pennies per part. For plastic parts the crossover is typically 200-2,000 units.
Cost comparison at a glance
| CNC Milling | Injection Molding | |
|---|---|---|
| One-off part | $40-150 | n/a (mold $2k-20k) |
| Batch of 100 (per part) | $15-60 | $1-5 |
| Production volume (per part) | $8-30 | $0.3-3 |
| Typical lead time | 2-5 days | 3-8 weeks first part |
| Tolerance | ±0.05 mm | ±0.1 mm |
| Materials | aluminum, steel, brass, titanium, plastics | PP, ABS, PC, nylon, TPE and hundreds more |
These are indicative service-market ranges for a palm-sized part — your own costs depend on your machines, rates and region. Both calculators below let you price the same part both ways with your numbers and see the crossover for yourself.
Choose CNC Milling when…
- metals or engineering plastics in low volumes
- tolerances tighter than molding can hold
- bridge production while the mold is built
- design changes still possible
Choose Injection Molding when…
- plastic parts in the thousands
- thin walls and complex surfaces at scale
- unit economics matter more than startup cost
- consistent, repeatable production
Price your part in seconds with the free CNC Milling cost calculator — upload your file, quantities and machine time are estimated automatically.
Open the CNC Milling cost calculator →Price your part in seconds with the free Injection Molding cost calculator — upload your file, quantities and machine time are estimated automatically.
Open the Injection Molding cost calculator →Put AI-powered instant quoting on your own website
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